Pier Luigi de Borgia, 1st Duke of Gandía (Spanish: Pedro Luis de Borja, Catalan: Pere Lluís de Borja, Latin: Petrus Ludovicus de Boria; c. 1468 – 3 September 1488) was the illegitimate son of Cardinal Rodrigo Borgia (later Pope Alexander VI) and a member of the House of Borgia. He was the first duke of Gandía, a duchy in the Kingdom of Valencia that King Ferdinand II of Aragon re-established in 1485 as a favour to his father.
Duke of Gandía (Valencian: Ducat de Gandia, IPA: [duˈkad de ɣanˈdi.a]) is a title of Spanish nobility that was first created in 1399 by Martin of Aragon and granted to Alfonso of Aragon and Foix. It has its origin in the lordship of Gandía created in 1323 by James II of Aragon. Later, having no direct descendants, the title passed from the House of Barcelona to the House of Trastámara.
The title was re-established in 1483 by Ferdinand II of Aragon as a favour to Rodrigo Cardinal Borgia for his son Pier Luigi Borgia. The dukedom then went to Pier Luigi's half-brother Giovanni Borgia. He was assassinated, and his young son inherited the title. The fourth duke was the religious figure Francesco Borgia. After the death of his wife, with whom he had a large family, he became a Jesuit.